Method and apparatus for making nugget ice in a refrigerator

ABSTRACT

An ice making system for producing on-demand nugget ice in a refrigerator includes an auger type icemaker having a double thin-walled cylindrical flooded, evaporator and a chilled water reservoir connecting to refrigerated rater. When ice is demanded, the evaporator is then connected to the refrigeration circuit through a dedicated refrigerant control device to achieve −40° F. rapid cooling. With near 32° F. chilled water, a layer of ice can form on the evaporator surface within 1 minute. Meanwhile a rotating auger scrapes ice layer into flake ice and compresses it through an extrusion and delivery tubing to form cylindrical ice. Then it breaks into nugget ice in the tubing and drops in an ice container.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not Applicable

FIELD OF THE INVENTION

This invention generally relates to ice making systems, and more particularly to producing on-demand nugget ice in a refrigerator.

BACKGROUND OF THE INVENTION

Crescent ice is widely available in a refrigerator for home use. The automatic icemaker in a refrigerator produces crescent ice cubes from an ice mold and the ice mold must be installed at a location below freezing temperature. Water is filled in the ice mold and then freezes for about an hour to become solid ice. A heater located at the bottom of the mold is turned on at around 14° F. by a thermostat to separate ice cubes from the mold. Since the ice production is so slow, ice must be produced all the time and stored in an ice bin below freezing temperature for daily use. The other disadvantage includes taking plenty food storage space by the ice bin in the refrigerator.

Different from crescent ice, nugget ice is very popular for commercial use, which is soil and chewable. Nugget ice cools beverages much faster than crescent ice.

Nugget ice is made by compressing and extruding flake ice. Flake ice is produced on a freezing surface and scraped by a rotating auger. Nugget ice can be produced much faster than crescent ice.

Because of complexity stand-alone commercial or residential nugget ice machines are supplied at very expensive prices. If nugget ice can be produced in a refrigerator, it will provide an economical way to produce nugget ice and bring an unprecedented experience to consumers.

In current nugget ice machines, i has to be stored in an insulated ice bin near room temperature for use in high demand. Water produced from melted ice must be drained or reused. However it is neither efficient nor convenient in a refrigerator Furthermore, nugget ice can't be stored below freezing temperature in a refrigerator, otherwise it rill freeze together.

Therefore, a nugget ice making system for particular t s refrigerator which can quickly produce on-demand nugget ice without using an ice storage bin, would be desirable and is not currently available. It is an object of the invention to provide an economical method and apparatus for producing on-demand nugget ice in a refrigerator.

BRIEF SUMMARY OF THE INVENTION

The present invention is to provide an ice making system that can quickly produce on-demand nugget ice in a refrigerator, which includes an auger type icemaker having a flooded cylindrical evaporator and a rotating auger, a gear motor, a chilled water reservoir having a float valve, an ice container and a dedicated refrigerant control device having a 3-way solenoid valve,

The flooded evaporator has double thin-walled stainless steel cylinders including an outer cylinder and an inner cylinder. The space between the two cylinders is filled with −40° F. liquid refrigerant. The evaporator maintains liquid only to have it flooded. The flooded evaporator provides rapid cooling. The rotating auger is located in the center of the inner cylinder and driven by the gear motor.

The chilled water reservoir has an inlet that connects refrigerated water in the refrigerator. It also has an outlet and a vent that connect the inside space of the inner cylinder of the evaporator at the same time to maintain the inner cylinder full of chilled water at all times. Furthermore, the float valve prevents the water reservoir from overfilling. The chilled water achieves quick ice forming.

There is a dedicated refrigerant control device to connect the icemaker evaporator to the refrigeration circuit through a 3-way solenoid valve. The refrigerant control device is optimized for operating at −40° F. evaporating temperature to produce very cold liquid refrigerant. A liquid accumulator is used in the refrigeration circuit to prevent excessive liquid refrigerant from returning to the compressor.

When ice is demanded, the 3-way solenoid valve is open to connect the icemaker evaporator to the refrigeration circuit and disconnect the refrigerator evaporator at the same time. Within 1 minute, a layer of ice will be formed on the inside surface of the inner cylinder of the evaporator. Meanwhile, the auger spins and scrapes ice layer into flake ice and compresses it through an extrusion and delivery tubing to form cylindrical ice. Then cylindrical ice breaks into nugget ice in the tubing and drops in an ice container.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the preferred embodiment of the present invention

FIG. 2 is an exploded view of the icemaker of the preferred embodiment of FIG. 1

FIG. 3 is a sectional view of the evaporator of the preferred embodiment of FIG. 2

FIG. 4 is a perspective view of the water reservoir with the ice container of the preferred embodiment of FIG. 1

FIG. 5 is a schematic diagram of the refrigeration circuit in the preferred embodiment of FIG. 1

DETAILED DESCRIPTION OF THE INVENTION

The preferred embodiment of the present invention is shown in FIG. 1. An ice making system that can quickly produce on-demand nugget ice in a refrigerator, which includes an auger type icemaker 100 (shown in greater detail in FIG. 2) having a flooded cylindrical evaporator 150 (show in greater detail in FIG. 2 & 3) with insulation on the outside (not shown) a rotating auger 110 (shown in greater detail in FIG. 2), a gear motor 200, a chilled water reservoir 300 (shown in greater detail in FIG. 4) having a float valve 304 (shown in greater detail in FIG. 4), an ice container and a dedicated refrigerant control device 505 (shown in FIG. 5) having a 3-way solenoid valve 509 (shown in FIG. 5).

As shown in FIG. 2, the flooded evaporator 150 has double thin-walled stainless steel cylinders, which includes an outer cylinder 104 and an inner cylinder 105. The two cylinders are welded to two copper flanges 108 and 109 to form a closed space. The space between the two cylinders is filled with −40° F. liquid refrigerant through an inlet 106 at the bottom and an outlet 107 at the top. The evaporator 150 is constructed in such a way to hold only liquid and allow vapor to escape that it is flooded. The use of flooded evaporator 150 provides rapid cooling.

The inside space of the inner cylinder 105 is water sealed. On one end it is bolted with a shaft bearing seat 101 through flange 108, and on other end it is bolted with a shaft seal seat 102 through flange 109. Both seats 101 and 102 are made of plastic. A shaft bearing (not show inserted in the bearing seat 101 and a shaft seal (not shown) is inserted in the seal seat 102.

The rotating auger 110 is located in the center of the inner cylinder 105 and supported by the shaft bearing seat (101) and the shaft seal seat 102). The auger 105 is driven by the gear motor 200 (shown in FIG. 1) through a key.

As shown in FIG. 3, a piece of stainless steel tubing 103 is welded on the inner cylinder 105 of the evaporator 150. One end of the tubing is located inside the inner cylinder and it is shaped as a cutter 111 to break compressed cylindrical ice.

As shown in FIG. 4, the chilled water reservoir 300, which is located above the flooded evaporator 100, has an inlet 303 located at its middle point to receive refrigerated water (not shown) in the refrigerator. The water reservoir 300 also has an outlet 301 and a vent 302 located at its lowest and highest points to connect the inside space of the inner cylinder 105 of the evaporator 150 at its lowest, and highest points respectively to maintain the inner cylinder 105 full of chilled water at all times. The float valve 304 prevents the water reservoir from overfilling. The chilled water achieves quick ice forming.

As shown in FIG. 5, there is a dedicated refrigerant control device 505 to connect the icemaker evaporator 150 to the refrigeration circuit 500 through a 3-way solenoid valve 509. The refrigerant control device 505 is optimized for operating at −40° F. evaporating temperature to produce very cold liquid refrigerant. The icemaker evaporator 150 is connected to the refrigerator evaporator 506 in series to allow most refrigerant storing in the refrigerator evaporator in case the refrigerator calls for cooling. A liquid accumulator 508 is used in the refrigeration circuit 500 to prevent excessive liquid refrigerant from returning to the compressor 501.

In the preferred embodiment, when ice is demanded, the 3-way solenoid valve 509 is open to connect the icemaker evaporator 507 to the refrigeration circuit 500 and disconnect the refrigerator evaporator 506 at the same time. Within 1 minute, a layer of ice will be formed on the inside surface of the inner cylinder 105. Meanwhile, the rotating auger 110 spins and scrapes ice layer into flake ice and compresses it through an extrusion and delivery tubing 103 to form cylindrical ice. Furthermore, cylindrical ice breaks into nugget ice the tubing 103 and drops in the ice container 350.

In the preferred embodiment, water from melted ice in the ice container 350 returns to the chilled water reservoir 300 through the holes 351 o the bottom. This prevents water from dripping in the refrigerator.

Therefore, the advantage of the present invention is to provide a method and apparatus to produce on-demand nugget ice in a refrigerator using a specially designed auger type icemaker. The preferred embodiment of this invention is particularly suited to a refrigerator in which the refrigeration system already exists. However, it is to be understood that various modifications may be used without departing from the principle of the present invention scope.

Accordingly, the breadth and scope of invention should be limited only by the scope of the claims appended hereto. 

1. An ice making system that can produce nugget ice in a refrigerator comprising: an auger type icemaker; whereby said auger type icemaker is used to produce nugget ice in the refrigerator.
 2. An ice making system of 1, which can produce on-demand nugget ice within one minute in a refrigerator comprising: an auger type icemaker including a liquid flooded cylindrical evaporator and a rotating auger; a gear motor connected to said rotating auger; a water reservoir with a float valve connected to refrigerated water and said liquid flooded cylindrical evaporator; an ice container located above said water reservoir; a dedicated refrigerant control device having a separate capillary tube and a 3-way solenoid valve connected to said liquid flooded cylindrical evaporator; whereby said liquid flooded cylindrical evaporator is connected to the refrigeration circuit through said dedicated refrigerant control device having a separate capillary tube to achieve quick cooling. With refrigerated water, a layer of ice can form on the inside surface of the inner cylinder of said liquid flooded cylindrical evaporator within 1 minute. Meanwhile said rotating auger scrapes the ice layers into flake ice and compresses the flake ice through an extrusion and delivery tubing to form cylindrical ice. Then the cylindrical ice breaks into nugget ice in said extrusion and delivery tubing and drops in said ice container.
 3. An ice making system of claim 2, wherein said liquid flooded cylindrical evaporator has stainless steel double thin-walled cylinders including an outer cylinder and an inner cylinder. The space between the two cylinders is sealed and filled with −40° F. liquid refrigerant. Said liquid flood cylindrical evaporator is constructed with an inlet at the bottom and an outlet at the top that only liquid will be kept but vapor will be allowed to escape.
 4. An ice making system of claim 3, wherein a piece of stainless steel tubing is welded on the inner cylinder of said liquid flooded cylindrical evaporator. One end of said piece of stainless steel tubing that is located inside the inner cylinder is shaped as a cutter that is used to break the compressed cylindrical ice.
 5. An ice making system of claim 2, wherein said water reservoir located above said liquid flooded cylindrical evaporator is connected to refrigerated water in the refrigerator. Said float valve prevents said water reservoir from overfilling and maintains the inner cylinder full of refrigerated water.
 6. An ice making system of claim 2, wherein water from melted ice returns to said water reservoir to avoid water dripping in the refrigerator.
 7. An ice making system of claim 2, wherein said dedicated refrigerant control device having a separate capillary tube connects said liquid flooded cylindrical evaporator to the refrigeration circuit controlled by said 3-way solenoid valve. Said dedicated refrigerant control device having a separate capillary tube is optimized for operating at −40° F. evaporating temperature to produce −40° F. liquid refrigerant. 